Collapsible float for aircraft



April 1946- T. P. HALL ET AL 2,399,346

- 'COLLAPSIBLE FLOAT I Filed April 26, 1944 45heets-Sheet l April 30, 1946.

T. P. HALL ET AL COLLAPSIBLE FLOAT FOR AIRCRAFT Filed April 26', 1944 4Sheets-Sheet 2 April 30, 1946. 4 T. P. HALL ET AL 2,399,345

- COLLAPSIBLE FLOAT FOR AIRCRAFT Filed April 26, 1944 4 Sheets-Sheet 3 m2 hW\ 3 MN 4N L I 4 mm m A fie IT W April 30, 1946.

T. P. HALL'ETAL COLLAPSIBLE FLOAT FOR AIRCRAFT Filed April .26, 1944 4 Sheets-Sheet 4 Patented Apr. 30, 1946 UNITED. STATES PATENT CQLLAPSIBLE FLOAT FOR AIRCRAFT Theodore P. Hall and Bruce Smith, San Diego,

alif., assignors to Consolidated Vultee Aircraft Corporation, San Diego, Calif., a corporation of Delaware Application April 26, 1944, Serial No. 532,698

10 Claims.

' the hull.

Another object of the invention is to provide a float which comprises a retractable top deck, a hull retractably connected to the top deck, and a collapsible enclosure between the deck and the hull, and means controlled by the retraction of the top deck, for collapsing the float.

Another object of the invention is to provide a. collapsible float which comprises a, rigid hull with a buoyant water-tight compartment. therein for buoyancy, a retractable top deck, and a collapsible envelope for providing a chamber between the hull and the top deck for additional buoyancy.

Another object of the invention is to rovide a collapsible float which comprises a rigid hull, a rigid top deck, and supporting and retracting connections between the top deck and the hull which are adapted to resist the heavy impacts against the hull to which it is subjected in use.

Another object of the invention is to provide a collapsible float which comprises a retractable top deck, a hull into which the top deck can be folded, and provided with a rim shaped to conform substantially to the wing of the aircraft for minimizing parasitic drag by the float while the aircraft is in flight.

Another object of the invention is to provide aircraft equipped with a pivoted drag-panel having acollapsible float pivoted thereto to swing transversely with means for controlling the transverse tilting of the float.

Other objects of the invention will appear from the detailed description.

The invention consists in the several novel features hereinafter set forth and more particularly defined by claims at the conclusion hereof.

In the drawings:

Fig. 1 is a perspective of a collapsible float embodying the invention, parts being broken away for better illustration.

Fig. 2 is a section through the wing of an airplane and the collapsible float in its retracted position.

Fig. 3 is a transverse section of the float taken on line 3-3 of Fig. 1.

Fig. 4 is a side elevation of the gearing mounted on the top deck for shifting the hull relatively to said deck.

Fig. 5 is a front elevation of the parts illustrated in Fig. 4, parts being broken away for illus- I trative purposes. Fig. 6 is a longitudinal section through an airplane wing illustrating the retracting mechanism for the collapsible float, the latter being shown in its lowered position.

Fig. 7 is a section on line 7-7 of Fig. 3, illustrating the valve for controlling the flow of air into and from the chamber between the top deck and the hull.

Fig. 8 is a longitudinal section of the float in its collapsed position. 1

Fig. 9 is a perspective of the float in its 001- v lapsed position.

The invention is exemplified as applied to a wing at of an airplane which is equipped with a drag-panel b for retractably carrying the float. The drag-panel b is fulcrumed at b to swing spanwise of and downwardly from the wing from a recess in the lower side of the wing, to lower the float. The collapsible float is pivotally supported from the distal end of the drag-panel b and is retractable as an entity by the drag-panel. The

- collapsible float comprises, generally, a rigid top deck which is pivotally connected to the dragpanel, a rigid hull which is shiftable to and from the top deck for collapsing the float, and a flexible and collapsible enclosure or body between the hull and the top deck. The structure includes mechanism for concurrently retracting the hull to the top deck with the swinging retractable movement of the drag-panel so that when the float is in its entirely lowered position by the swinging movement of the drag-panel, the float will be automatically expanded, and during the retraction of the float to the wing will be collapsed. The longitudinal axis of the float extends transversely or chordwise of the wing. The top deck of the float is foldable into the hull of the float and the rim of the latter has a contour which conforms substantially to and fits against the under surface of the aircraft-wing and fairing thereon for minimizing parasitic drag. Thehull is shaped for the necessary hydrodynamic qualities and constructed to resist the impact and shock loads during take-oil and landing of the airplane.

The hull of the collapsible float comprises a bottom which is formed of rigid sheet metal plates iii; a keel which extends the length of the hull and is composed of bars I6 having flanges I! underlying the sheets I5; a pair of upper anglebars l8, and vertical plates l9 secured to the vertical flanges of bars "5 and I8; a sub-deck 20 extending across the hull and composed of sheets 2i of metal secured by comer-plates 23 to the plates 2| and to a vertically extending rim 22 of the hull; and transverse ribs 24 formed of flanged plates secured to the bottom plates l8 and to the plates 2! of the sub-deck. The bow portion .of the hull is also reinforced by transverse plates 21. The bottom of the hull and sides 22 are curved longitudinally between the bow and stem for hydrodynamic qualities, and chines 28 are secured to the corners between the bottom and side of the hull. The rim of the sides 22 of the hull is shaped to substantially conform to and fit against the underface of the wing a and the fairing a. The space between the sub-deck 28 and the bottom ii of the hull forms a compartment 26 of substantial buoyant capacity, the structural parts around said compartment being suitably Joined together to render the compartment water-tight.

Top deck 28 of the float is formed of sheet metal which is ribbed as at 29 and has a downturned rim 38 and is reinforced by angle-bars 3| and 32. The margin of the top deck has a contour which permits it to be shifted into the area of the hull between the side 22 and adjacent the sub-deck 28. The central portion of the top deck has riveted to its top side stiffening bars 33. A front mooring ring 34 and a rear mooring rin 35 are attached to the top deck.

The space between the hull and the top deck 28 is enclosed by an envelope 38 which forms a collapsible enclosure'between the hull and the top deck and is formed of suitable flexible material to permit the top deck to be folded into the hull. The envelope 38 extends around the sides, bow and stern of the hull and the deck 28. Envelope 36 is secured and sealed as at 31 around the rim of the top deck and its lower margin is secured and sealed, as at 38, around the inner face of the hull-sides 22I The envelope 38, top deck 28 and the sub-deck 29 form a collapsible compartment 39 which provides additional buoyancy to that provided by compartment 26 for the float. A suitable valve 40 is provided at the top deck 28 which ermits air to enter thecompartment 39 when the hull is lowered away from the top deck 28 and to escape when the float is collapsed.

The hull is connected to the top deck 28 for retraction to and separation from said deck by a transversely aligned front pair of strut-links 42 and a rear pair of transversely aligned strut-links 58. When the hull is lowered away from the top deck 28. the links are inclined forwardly and downwardly from the top deck to the hull to resist the impact against, and shock loads imparted to, the hull. The links 42 are substantially parallel with the links 50. Each of the strutlinks 42, 58 is bifurcated and has the lower end of its members joined together by a sleeve 42'. A sleeve 42 is welded to the upper end of each member of strut-links 42 and 58; Each sleeve 42 is pivotally connected by a pin 43 to a bracket 44 which is fixedly secured to longitudinally extending reinforcing bars 45 which are fixedly secured to the sub-deck 28. The lower ends of the strut-links 58 are similarly pivoted by pins 43 to brackets 44. The upper end of each inner member of said link is pivoted on a transversely extending shaft 48 which is lournaled in brackets 49 which are fixedly secured to the top deck 28 and to stiffening bars 33. The sleeves 42"- cf the outer members of links 58 are pivoted by pins 48 to brackets 41 which are fixed to the top deck 28.

The float in its entirely is pivotaliy supported from the panel I) on an axis which extends longitudinally of the float. The front co ner 01 the panel b is connected by a pivot I4 to a bracket I3 which is fixedly secured to the top deck 28. The rear corner of the drag-panel 1: supports the shaft 5: which is mounted in brackets 88 which are secured to the top side of the deck 28. Shaft 52 and pivot 54 are coaxial and constitute a pivotal connection between the distal end of the drag-panel b and the top deck 28.

The invention utilizes the swinging movement of the drag-panel b for expanding and collapsing the float so that, as said panel is swung downwardly to lower the float, the hull will be concurrently separated from the top deck 28 to expand the float and extend the compartment 38 to provide additional buoyancy and for concurrently retracting the hull to the top deck 28 and collapse the float when the drag-panel isswung upwardly to retract the top deck. Mechanism for this purpose comprises a spiral-gear segment 18 which is fixed in a forked pivot lug or bracket I8 on the rear corner of the drag-panel b by through ins 71 so that said segment will rotate with the drag-panel around shaft 52; a spiral gear segment 18 which meshes with gear segment I8 and is keyed to the shaft 48 which is journaled in brackets 49 and on which the upperends of the inner member of strut links 88 are pivoted; and a toggle-lever which functions as a jointed strut and is o erable by the gear-segment I8 to lower the hull away from the deck 28 and to retract the null for collapsing the float. The toggle-lever comprises dual members and each member comprises an upper tubular section 82, the upper end of which is flattened and fixedly secured by pins 83 for rotation with the segment I8, a lower tubular section 84, the lower end of which is flattened and pivotally connected by a pin 85 to a bracket 86 which is fixed to the sub-deck 20, and a pivotal Joint between each of the upper and lower sections of each member, formed by a pin 81 and lugs 88, 89 welded to the sections, respectively, and provided with abutments which arrest the sections when they are in dead center relation between pivot 85 and shaft 48.

When the drag-panel is positioned in the recess of the wing a and is swung downwardly spanwise of the wing, the gear segment I5 swings with the drag-panel b on the shaft 52, the axis of which extends longitudinally of the float. Segment 15 rotates the gear segment 18 and shaft 48 which extends transversely of the float and swings the lever-sections 82, which are fixed to segment 18, downwardly and rearwardly to operate the lower sections 84 of said lever until the meeting ends of the-upper and lower lever sections Pass into abutting relation and are thereby locked against further rearward movement. During this operation, the strut-links 42, maintain th deck 28 and the hull in anguular relation. The hull, concurrently with the lowering of the top deck 28, will be lowered relatively to the top deck by the toggle-lever to extend the flexible envelope 38 and form the buoyancy compartment 39 so that when the float is lowered it will have the combined buoyancy produced by the compartments 28 and 39. The toggle-lever composed of sections 82 and 84 will then be locked in one direction to retain the hull in separated relation from the top deck. The links 42, 88 will be positioned at an angle to transmit thrust from the bull to the top deck and to resist impact loads on the hull while landin 'the aircraft.

When the drag-panel is in its lowered position and the float is in position for landing and the drag-panel b is swung upwardly to retract the float, the gear segment 15 will be reversely ro- 4 tated with the panel b and rock the segment IB to swing the upper lever-sections 82 forwardly until the float has been completely collapsed, the links 92 and Bil maintaining the angular relation of the top deck and the hull during such retraction. This operation occurs concurrently with the retraction of the drag-panel. When the draglink reaches its fully retracted position in the recess in the wing a, the rim of the side 22 of the hull which conforms substantially to the under camber surface of the wing. a will flt against said surface and the fairing a to minimize the parasitic drag of the float during flight. The top deck 28 will be folded into the hull above the sub-deck and the strut-links 62, Eli and the toggle-lever will be folded into and confined in the space above the sub-deck in the hull.

The drag-panel b is pivotally supported at b from the wing structure of the airplane. The wing structure and drag-panel b are also connected by apair'of strut-links 96 which are pivoted to each other at 96'. The lower of said links 96 is pivoted at 97 to the drag-panel and the upper end of the upper of said links is pivoted to the wing structure at 9B. This linkage composed of links 96 is foldable and operable by power means for raising and lowering the dragpanel and the float suspended therefrom. The power means comprises a hydraulic cylinder 66 which is pivoted attl to the upper link 96 and a piston slidable in cylinder 66 and on a stem 68. The outer end of stem 68 is pivoted at m to a crank arm b which is rigidly attached to the drag-panel. When the drag-panel is lowered and hydraulic fluid delivered into cylinder 66 to move the piston and its stem 88' outwardly from the cylinder, pivots 61 and 10 will be spread apart to fold the links 99 and swing the dragpanel upwardly until the links have been collapsed and the drag-panel lies within the recess in the wing, as well understood in the art. intermediate position of the drag-panel and the linkage is illustrated in dotted lines in Fig. 6. In lowering the drag link, the hydraulic device is reversely operated to operate the links 96 and the drag-panel b to the position illustrated in full lines in Fig. 6. The links 91 are aligned and operate as a foldable strut for securing the dragpanel b against lateral swinging when said panel is in its vertical position.

The pivotal connection between the drag-panel b and the top deck 29 extends longitudinally of and is located at the transverse center of said deck and does not prevent transverse tilting of the float. The transverse relation between the float and the drag-panel is controlled by a link 9| which has one of its ends adjustably pivoted, as at 92, to a bracket 93 which is secured to the deck 28 and to a reinforcing bar 96 which is also flxed to the top deck. The other end of link 9! is pivoted at 95 to the lower link 96 of the folding strut.

An arm 99 is fixed to the shaft 48 which rotates with gear segment 18, for operating valve 40 to admit air to the chamber 39 during the lowering of the drag-panel, to close the valve atthe end of the lowering movement of the float and to open said valve for permitting air to escape from chamber 39 during the retraction of the float. Valve 90 is pivoted at 40 to the top deck to open rearwardly to avoid scooping spray into the chamber 39 in the float. The arm 99 automatically controls the opening and closing of the valve 49 during the raising and lowering movements of the float.

The invention exemplifies a collapsible float which comprises: a hull with a built-in water.- tight chamber, a top deck and a collapsible envelope between the top deck and the hull for providing an additional chamber for maximum buoyancy capacity; expanding and contracting mechanism between the top deck and the hull which is operable by the movements of the drag-panel; a top deck which is foldable into the hull with the expanding mechanism between them; which flts the lower camber surface of the airplane wing for minimizing parasitic drag during flight, and a construction adapted to effectively resist impact stresses and loads when the float strikes the water.

The invention is not to be understood as restricted to the details set forth, since these may be modified within the scope of the appended claims without departing from the spirit and scope of the invention.

Having thus described the invention, what we claim as new and desire to secure by Letters Patent is:.

1. In aircraft, the combination with a retract pended from and for retraction to the top deck,

a collapsible closure between and providing a chamber between the top deck and the hull, means operable by the swinging movements of the panel for retracting the bull to the top deck, a valve for admitting air to and from said chamher, and means also operable by the swinging movement of the panel, for controlling said valve.

2. A retractable float for an airplane comprising: a rigid top deck, means for retractably supporting the deck from an airplane, a rigid hull including a bottom and sides having a rim substantially conforming in contour to a portion of the airplane, movably supported from the deck and forming a compartment with an open top, a flexible envelope forming a collapsible closure between the rigid deck and the sidesof the hull, the deck and envelope being foldable into the compartment in the hull, and means for spreading apart the deck and the hull to expand the float when the supporting means is operated to extend the float and for folding the deck and envelope into the compartment in the hull and moving the rim to said portion of the airplane when the supporting means is retracted.

3. A retractable float for an airplane comprising: a rigid top deck, a drag-panel for retractably and pivotally supporting the deck from an airplane, a rigid hull including a bottom and sides having a rim substantially conforming in contourto a portion of the airplane, movably supported from the deck and forming a compartment with an open top, a flexible envelope forming a collapsible closure between the rigid deck and the sides of the hull, the deck and envelope being foldable into the compartment in the hull, and means for spreading apart the deck and the hull to expand the float when the dragpanel is operated to extend the'float and for folding the deck and envelope into the compartment in the hull and moving the rim to said portion of the airplane when the drag-panel is retracted.

4. A retractable float for anairplane comprising: a rigid top deck, a drag-panel for retractably and pivotally supporting the deck from an airplane, a rigid hull including a bottom and sides having a rim substantially conforming in contour to a portion of the airplane, movably supported from the deck and forming a compartment with an open top, a flexible envelope forming a collapsible closure.between the rigid deck and the sides of the hull, the deck and-envelope being foldable into the compartment in the hull, and means for spreading apart the deck and the hull to expand the float when the dragpanel is operated to extend the float and for folding the deck and envelope into the compartment in the hull and moving the. rim to said portion of the airplane when the drag-panel is retracted, said means comprising a toggle-lever and strut links between the hull and the deck.

5. A retractable float for an airplane comprising: a rigid top deck, means for retractably supporting the deck from an airplane, a rigid hull extended longitudinally of the airplane, including a bottom and sides having a rim substantially conforming in contour to a portion of the airplane, movably supported from the deck and a transverse plate adjacent the bow of the hull, and forming a compartment with an open top, a flexible envelope forming a collapsible closure be-- tween the rigid deck and the sides of the hull, the deck and envelope being foldable into the compartment in the hull, and means for spreading apart the deck and the hull to expand the float when the supporting means is operated to extend the float and for folding the deck and envelope into the compartment in the hull and moving the rim to said portion of the airplane when the supporting means is retracted, said means including means for relatively shifting the hull and deck to fold the deck in the compartment below the top of the transverse plate.

6. A collapsible float for an airplane provided with a retractable drag-panel pivotally suspended from and to swing transversely of the airplane, comprising: a rigid hull arranged to extend longitudinally of an airplane as described, including a bottom and sides forming a compartment therein with an open top, a longitudinally extending rigid top deck adapted to be folded into the compartment in the hull, means for pivotally supporting the top deck from the drag-panel substantially at its transverse center on an axis extending longitudinally of the hull, a flexible envelope forming a collapsible enclosure between the top deck and the hull, and means operable by the transverse swinging movement of the drag-panel for lowering the hull away from the deck to expand the float and for folding the deck into the compartment in the hull when the dragpanel is retracted.

'7. A collapsible float for an airplane provided with a retracable drag-panel pivotally suspended from and to swing transversely of the airplane, comprising: a rigid hull arranged to extend longitudinally of an airplane as described, including a rigid bottom and sides forming a compartment therein with an open top, a longitudinally extending rigid top deck adapted to be folded into the compartment in the hull, means for pivotally supporting the top deck from the dragpanel substantially at its transverse center to swing on an axis extending longitudinally of the hull, a flexible envelope forming a collapsible enclosure between the top deck and the hull, and

means operable by the transverse swinging movement of the drag-panel for lowering the hull away from the deck to expand the float and for the deck and the hull.

8. A collapsible float for an airplane provided with a retractable drag-panel pivotally suspended from and to swing transversely of the airplane, comprising: a rigid hull arranged to extend longitudinally of an airplane as described, including a bottom and sides forming a compartment therein with an open top, a longitudinally extending rigid top deck adapted to be folded into the compartment in the hull, means for pivotally supporting the top deck from the drag-panel substantially at its transverse center to swing on an axis extending longitudinally of the airplane. a flexible envelope forming a collapsible enclosure between the top deck and the hull, and means including a longitudinally swinging toggle-lever operable by the transverse swinging movement of the drag-panel for lowering the hull away from the deck to expand the float and for folding the deck into the compartment in the hull when the drag-panel is retracted.

9. A collapsible float for an airplane provided with a retractable drag-panel pivotally suspended from and to swing transversely of the airplane, comprising: a rigid hull arranged to extend longitudinally of an airplane as described, including a rigid bottom and sides forming a compartment therein with an open top, a longitudinally extending rigid top deck adapted to be folded into the compartment in the hull, means for pivotally supporting the top deck from the drag-panel substantially at its transverse center to swing on an axis extending longitudinally of the hull, a flexible envelope forming a collapsible enclosure between the top deck and the hull, means operable by the transverse swinging movement of the drag-panel for lowering the hull away from the deck to expand the float and for folding the deck into the compartment in the hull when the drag panel is retracted, and means for holding the float against tilting on said longitudinal axis during extension and retraction of the float.

10. A retractable float for an airplane comprising: a rigid top deck, means for retractably supporting the deck from an airplane, a rigid hull including a bottom and sides having a rim substantially conforming in contour to a portion of the airplane, and a sub-deck movably supported from the top deck forming a compartment with an open top above the sub-deck, a flexible envelope forming a collapsible closure between the rigid top deck and the sides of the hull, the top deck and envelope being foldable into the compartment in the hull and over the sub-deck, and means for spreading apart the top deck and the hull to expand the float when the supporting means is operated to extend the float and for folding the top deck and envelope into the compartment in the hull, and moving the rim to said 7 portion of the airplane when the supporting means is retracted, said last means including links foldable between the sub-deck and the top deck.

THEODORE P. HALL. BRUCE SMITH. 

